gene therapy


gene therapy
gene therapy n the insertion of usu. genetically altered genes into cells esp. to replace defective genes in the treatment of genetic disorders or to provide a specialized disease-fighting function (as the destruction of tumor cells)
gene therapist n

* * *

treatment directed to curing genetic disease by introducing normal genes into patients to overcome the effects of defective genes, using techniques of genetic engineering. The most radical approach would be to do this at a very early stage in the embryo, so that the new gene would be incorporated into the germ cells (ova and sperm) and would therefore be inheritable. However, this approach is not considered to be either safe or ethical, because the consequences would affect all descendants of the patient, and it is not being pursued. In somatic cell gene therapy the healthy gene is inserted into somatic cells (such as the haemopoietic stem cell of the bone marrow) that give rise to other cells. All the surviving descendants of these modified cells will then be normal and, if present in sufficient numbers, the condition will be cured (the defective gene will, however, still be present in the germ cells).
At present, gene therapy is most feasible for treating disorders caused by a defect in a single recessive gene, so that the deficiency can be overcome by the introduction of a normal allele (therapy for disorders caused by dominant genes (e.g. Huntington's disease) would require the modification or replacement of the defective allele as its effect is expressed in the presence of a normal allele). Examples of such recessive disorders include adenosine deaminase (ADA) deficiency and cystic fibrosis. Gene therapy trials for the former condition have already begun: lymphocyte stem cells are isolated from the patient, using monoclonal antibody, and incubated with retrovirus that have been genetically engineered to contain the normal ADA gene (see vector). This gene thus becomes integrated into the stem cells, which - when returned to the patient's bone marrow - can then produce normal lymphocytes. A similar technique has been used in treating patients with severe combined immune deficiency and is feasible for other blood disorders, such as sickle-cell anaemia and thalassaemia.
Clinical trials for the gene therapy of cystic fibrosis involve using liposome to introduce the normal gene into the lungs of sufferers via an inhaler.
Gene therapy for certain types of cancer is also undergoing clinical trials. Here the approach is aimed at introducing into the cancer cells tumour-suppressing genes, such as p53 (which prevents uncontrolled cell division), or genes that direct the production of substances (such as interleukin 2) that stimulate the immune system to destroy the tumour cells.

* * *

manipulation of the genome of an individual to prevent, mask, or lessen the effects of a genetic disorder. The defective function may be replaced by introduction of genetic material into targeted cells, or the defective gene itself may be corrected by targeting a recombinational event to replace all or part of the defective gene with a normal DNA sequence.

Medical dictionary. 2011.

Look at other dictionaries:

  • Gene therapy — using an Adenovirus vector. A new gene is inserted into an adenovirull. If the treatment is successful, the new gene will make a functional protein. Gene therapy is the insertion, alteration, or removal of genes within an individual s cells and… …   Wikipedia

  • gene therapy — gene therapy. См. генотерапия. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • gene therapy — gene .therapy n [U] a way of treating certain diseases by using ↑genetic engineering …   Dictionary of contemporary English

  • gene therapy — gene ,therapy noun uncount a medical treatment in which genes are put into cells in the body in order to cure some types of illness …   Usage of the words and phrases in modern English

  • gene therapy — ► NOUN ▪ the introduction of normal genes into cells in place of missing or defective ones in order to correct genetic disorders …   English terms dictionary

  • gene therapy — n. the experimental treatment of a disease by the use of techniques associated with genetic engineering, as to modify or replace the disease causing genes of certain cells …   English World dictionary

  • gene therapy — treatment directed to curing genetic disease by introducing normal genes into patients to overcome the effects of defective genes, using techniques of genetic engineering. The most radical approach would be to do this at a very early stage in the …   The new mediacal dictionary

  • gene therapy — Med. the application of genetic engineering to the transplantation of genes into human cells in order to cure a disease caused by a genetic defect, as a missing enzyme. Cf. gene transfer. [1970 75] * * * or gene transfer therapy Introduction of a …   Universalium

  • gene therapy — noun : the insertion of usually genetically altered genes into cells especially to replace defective genes in the treatment of genetic disorders or to provide a specialized disease fighting function (as the destruction of tumor cells) • gene… …   Useful english dictionary

  • gene therapy — The proposed treatment of an inherited disease by the transformation of an affected individual with a wild type copy of the defective gene causing the disorder. In germ line (or heritable) gene therapy, reproductive cells are transformed; in… …   Glossary of Biotechnology


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.